In this reproduction of his original publication of 1649, Rene Descartes discusses how seekers of knowledge can best attain true insight of the world around them. Often referred to as simply the Discourse on the Method, this work is frequently cited as one of the most important to appear during the Enlightenment era. It discusses the ideal means through which those in search of knowledge can approach the world, and the practice of science, as a means of attaining true and (...) definitive insight. The Discourse on Method is influential chiefly for its role in establishing the scientific method; a technique which scientists have used to make valid discoveries over the centuries. Descartes instructs the reader to doubt everything, and to use this universal doubt as a starting point from which to approach a problem. In addition to matters of science, Descartes reflects upon his own personal, religious beliefs. In addition to his Method, Descartes also explains certain social and personal notions such as obeying the laws and statutes of his country and prioritizing self-advancement over the achievement of material wealth or fortune. Famous for including the much-quoted phrase "Je pense, donc je suis" - "I think, therefore I am" - the Discourse on Method today stands as a crucial cornerstone of countless educational courses on philosophy. (shrink)

The recent upsurge in “brain-training and perceptual-cognitive-training", proposing to improve isolated processes such as brain function, visual perception and decision-making, has created significant interest in elite sports practitioners, seeking to create an ‘edge’ for athletes. The claims of these related 'performance-enhancing industries' can be considered together as part of a process training approach proposing enhanced cognitive and perceptual skills and brain capacity, to support performance in everyday life activities, including sport. For example, the 'process-training industry' promotes the idea that playing (...) games not only makes you a better player, but also smarter, more alert, and a faster learner. In this position paper we critically evaluate the effectiveness of both types of process-training programmes in generalizing transfer to sport performance. These issues are addressed in three stages. First, we evaluate empirical evidence in support of perceptual-cognitive process training, and its application to enhancing sport performance. Second, we critically review putative modularised mechanisms underpinning this kind of training, addressing limitations and subsequent problems. Specifically, we consider merits of this highly specific form of training, which focuses on training of isolated processes such as cognitive processes (attention, memory, thinking) and visual perception processes, separately from performance behaviors and actions. We conclude that these approaches may, at best, may provide some 'general transfer' of underlying processes to specific sport environments, but lack 'specificity of transfer' to contextualize actual performance behaviors. A major weakness of process training methods is their focus on enhancing performance in body “modules” (e.g., eye, brain, memory, anticipatory sub-systems). What is lacking is evidence on how these isolated components are modified and subsequently interact with other process “modules”, which are considered to underlie sport performance. Finally, we propose how an ecological dynamics approach, aligned with an embodied framework of cognition undermines the rationale that modularised processes can enhance performance in competitive sport. An ecological dynamics perspective proposes that the body is a complex adaptive system, interacting with performance environments in a functionally integrated manner, emphasising that the inter-relation between motor processes, cognitive and perceptual functions and the constraints of a sport task is best understood at the performer-environment scale of analysis. (shrink)

Richard Jeffrey long held that decision theory should be formulated without recourse to explicitly causal notions. Newcomb problems stand out as putative counterexamples to this ‘evidential’ decision theory. Jeffrey initially sought to defuse Newcomb problems via recourse to the doctrine of ratificationism, but later came to see this as problematic. We will see that Jeffrey’s worries about ratificationism were not compelling, but that valid ratificationist arguments implicitly presuppose causal decision theory. In later work, Jeffrey argued that Newcomb (...) problems are not decisions at all because agents who face them possess so much evidence about correlations between their actions and states of the world that they are unable to regard their deliberate choices as causes of outcomes, and so cannot see themselves as making free choices. Jeffrey’s reasoning goes wrong because it fails to recognize that an agent’s beliefs about her immediately available acts are so closely tied to the immediate causes of these actions that she can create evidence that outweighs any antecedent correlations between acts and states. Once we recognize that deliberating agents are free to believe what they want about their own actions, it will be clear that Newcomb problems are indeed counterexamples to evidential decision theory. (shrink)

The Newcomb problem is analysed here as a type of common cause problem. In relation to such problems, if you take the dominated option your expected outcome will be good and if you take the dominant option your expected outcome will be not so good. As is explained, however, these arenot conventional conditional expected outcomes but `conditional evidence expected outcomes' and while in the deliberation process, the evidence on which they are based is only hypothetical evidence.Conventional conditional (...) expected outcomes are more sensitive to your current epistemic state in that they are based purely on actual evidence which is available to you during the deliberation process. So although they are conditional on a certain act being performed, they are not based on evidence that you would have only if that act is performed. Moreover, for any given epistemic state during the deliberation process, your conventional conditional expected outcome for the dominant option will be better than that for the dominated option. The principle of dominance is thus in perfect harmony with the conventional conditional expected outcomes. In relation to the Newcomb problem then, the evidence unequivocally supports two-boxing as the rational option. Yet what is advanced here is not simply a two-boxing strategy. To see why, two stages to the problem need to be recognised. The first stage is that which occurs before the information used by the predictor in making his predictions has been gained. The second stage is after this point. Provided that you are still in the first stage, you have an opportunity to influence whether or not the predictor places the $1m in the opaque box. To maximise the probability that it is, you need to commit yourself to one-boxing. (shrink)

The dominance conditional 'If I drink the contents of cup A, I will drink more than if drink the contents of cup B' is true if we know that the first cup contains more than the second. In the first part of the paper, I show that only one kind of theory of indicative conditionals can explain this fact — a Stalnaker-type semantics. In the second part of the paper, I show that dominance conditionals can help explain a long-standing mystery: (...) the question of how one-boxers and two-boxers are guided by conditionals to their respective answers to the Newcomb problem. I will suggest that both implicitly appeal to a decision theoretic principle I will call the Dominance Norm (DN), a principle that connects indicative dominance conditionals with rational courses of action. Finally, I show that DN in combination with a Stalnaker-type theory of indicatives commits us to the two-boxing answer in the Newcomb problem. (shrink)

실천적 결정이론은 크게 증거적 실천적 결정이론(Evidential Practical Decision Theory)과 인과적 실천적 결정이론(Causal Practical Decision Theory)으로 나뉜다. 그리고 잘 알려진 것처럼 전통적 뉴컴 문제는 우리가 왜 인과적 실천적 결정이론을 받아들여야 하는지에 대한 좋은 이유를 제공하는 것으로 이해된다. 그런데 최근 인식론에서는 실천적 결정 이론의 핵심적 아이디어가 합리적 믿음과 관련된 다양한 인식적 문제들에 적용되고 있다. 이러한 시도를 하는 이론을 ‘인식적 결정이론 (Epistemic Decision Theory)’이라고 부른다. 인식적 결정이론도 실천적 결정이론과 유사하게 증거적 인식적 결정이론(Evidential Epistemic Decision Theory)과 인과적 인식적 결정이론(Causal Epistemic Decision Theory)으로 나뉜다. 그런데 (...) 흥미롭게도 힐러리 그리브스 (Greaves, 2013)는 인식적 뉴컴 문제를 제시하고, 전통적 뉴컴 문제와 유사하게, 인식적 뉴컴 문제도 우리가 왜 증거적 인식적 결정이론보다 인과적 인식적 결정이론을 받아들여야 하는지에 대한 이유를 제공하는 것으로 이해될 수 있다고 주장한다. 이 논문의 목적은 과연 인식적 뉴컴 문제를 통해 인과적 인식적 결정이론이 증거적 인식적 결정이론보다 합리적 믿음의 본성을 더 잘 포착하는지 여부를 탐구하는 것이다. (shrink)

It is intuitively attractive to think that it makes a difference in Newcomb’s problem whether or not the predictor is infallible, in the sense of being certainly actually correct. This paper argues that that view is irrational and manifests a well-documented cognitive illusion.

There are two boxes in front of you and you are asked to choose between taking only box B or taking both box A and box B. Box A contains $ 1,000. Box B will contain either nothing or $ 1,000,000. What B will contain is (or will be) determined by Predictor, who has an excellent track record of predicting your choices. There are two possibilities. Either Predictor has already made his move by predicting your choice and putting a million (...) dollars in B iff he predicted that you will take only B (like in the standard Newcomb problem); or else Predictor has not yet made his move but will wait and observe what box you choose and then put a million dollars in B iff you take only B. In cases like this, Predictor makes his move before the subject roughly half of the time. However, there is a Metapredictor, who has an excellent track record of predicting Predictor’s choices as well as your own. You know all this. Metapredictor informs you of the following truth functional: Either you choose A and B, and Predictor will make his move after you make your choice; or else you choose only B, and Predictor has already made his choice. Now, what do you choose? (shrink)

A standard argument for one-boxing in Newcomb’s Problem is ‘Why Ain’cha Rich?’, which emphasizes that one-boxers typically make a million dollars compared to the thousand dollars that two-boxers can expect. A standard reply is the ‘opportunity defence’: the two-boxers who made a thousand never had an opportunity to make more. The paper argues that the opportunity defence is unavailable to anyone who grants that in another case—a Frankfurt case—the agent is deprived of opportunities in the way that advocates (...) of Frankfurt cases typically claim. (shrink)

Examples involving common causes — most prominently, examples involving genetically influenced choices — are analytically equivalent not to standard Newcomb Problems — in which the Predictor genuinely predicts the agent's decision — but to non-standard Newcomb Problems — in which the Predictor guarantees the truth of her predictions by interfering with the agent's decision to make the agent choose as it was predicted she would. When properly qualified, causal and epistemic decision theories diverge only on standard — not (...) on non-standard — Newcomb Problems, and thus not on examples involving common causes. (shrink)

Newcomb-like problems are classified by the payoff table of their act-state pairs, and the causal structure that gives rise to the act-state correlation. Decision theories are classified by the one or more points of intervention whose causal role is taken to be relevant to rationality in various problems. Some decision theories suggest an inherent conflict between different notions of rationality that are all relevant. Some issues with causal modeling raise problems for decision theories in the contexts where Newcomb (...) problems arise. (shrink)

Two-boxers in Newcomb Problems face the question: Why aren't you rich? The essay argues that one-boxers have a false sense of advantage. They fail to align their credences during deliberation with the credences they will have when they act. This puts them in violation of the so-called Principle of Reflection, and it exposes them to a dynamic Dutch Book that will leach any gains they achieve away.

Some philosophers worry that if modal realism is true, you have no reason to prevent evils. For if you prevent an evil, you’ll have a counterpart somewhere that allows a similar evil. And if you refrain, your counterpart will end up preventing the relevant evil. Either way one evil is prevented and one is allowed. Your act makes no difference. I argue that this is mistaken. If modal realism is true, you are in a variant of Newcomb’s Problem. (...) And if Lewis’ view about Newcomb’s Problem is true, then your act does make a difference and you should prevent the evil. (shrink)

It is commonly thought, in line with the position defended in an influential paper by David Lewis, that the decision problems faced in the prisoner’s dilemma and the Newcomb situation are essentially the same problem. José Luis Bermúdez has recently attacked the case Lewis makes for this claim. While I think the claim is false, I contend that Bermúdez’s reason for rejecting Lewis’s argument is inadequate, and then outline what I take to be a better reason for doing (...) so. (shrink)

This article proposes a new theory of rational decision, distinct from both causal decision theory (CDT) and evidential decision theory (EDT). First, some intuitive counterexamples to CDT and EDT are presented. Then the motivation for the new theory is given: the correct theory of rational decision will resemble CDT in that it will not be sensitive to any comparisons of absolute levels of value across different states of nature, but only to comparisons of the differences in value between the available (...) options within states of nature; however, the correct theory will also resemble EDT in that it will rely on conditional probabilities (not unconditional probabilities). The new theory gives a prominent role to the notion of a “benchmark” for each state of nature, by comparison with which the value of the available options in that state of nature are measured, and so it has been called the Benchmark Theory (BT). It is argued that BT gives the right verdict on the cases that seem to be counterexamples to CDT and EDT. Finally, some objections to BT are considered and answered. (shrink)

has offered evidential decision theorists a defence against the charge that they make unintuitive recommendations for cases like Newcomb's Problem. He says that when conditional probabilities are assessed from the agent's point of view, evidential decision theory makes the same recommendation as intuition. I argue that calculating the probabilities in Price's way leads to no recommendation. It condemns the agent to perpetual oscillation between different options. Price's Argument Instability Objections Conclusion.

In the Newcomb problem, the standard arguments for taking either one box or both boxes adduce what seem to be relevant considerations, but they are not complete arguments, and attempts to complete the arguments rely upon incorrect principles of rational decision making. It is argued that by considering how the predictor is making his prediction, we can generate a more complete argument, and this in turn supports a form of causal decision theory.

I apply some of the lessons from quantum theory, in particular from Bell’s theorem, to a debate on the foundations of decision theory and causation. By tracing a formal analogy between the basic assumptions of causal decision theory (CDT)—which was developed partly in response to Newcomb’s problem— and those of a local hidden variable theory in the context of quantum mechanics, I show that an agent who acts according to CDT and gives any nonzero credence to some possible (...) causal interpretations underlying quantum phenomena should bet against quantum mechanics in some feasible game scenarios involving entangled systems, no matter what evidence they acquire. As a consequence, either the most accepted version of decision theory is wrong, or it provides a practical distinction, in terms of the prescribed behaviour of rational agents, between some metaphysical hypotheses regarding the causal structure underlying quantum mechanics. (shrink)

David Lewis has argued that we can gain helpful insight to the Prisoners' Dilemmas that we face from the fact that Newcomb's Problems are easy to solve, and the fact that Prisoners' Dilemmas are nothing other than two Newcomb Problems side by side. The present paper shows that the Prisoners' Dilemmas that we face are significantly different from Newcomb Problems in that the former are iterated while the latter are not. Thus Lewis's hope that we can get (...) insight into the former from the latter is illusory. (shrink)

It is shown that the Fisher smoking problem and Newcomb's problem are decisiontheoretically identical, each having at its core an identical case of Simpson's paradox for certain probabilities. From this perspective, incorrect solutions to these problems arise from treating them as cases of decisionmaking under risk, while adopting certain global empirical conditional probabilities as the relevant subjective probabihties. The most natural correct solutions employ the methodology of decisionmaking under uncertainty with lottery acts, with certain local empirical conditional (...) probabilities adopted as the relevant subjective probabilities. (shrink)

It is shown that the Fisher smoking problem and Newcomb's problem are decisiontheoretically identical, each having at its core an identical case of Simpson's paradox for certain probabilities. From this perspective, incorrect solutions to these problems arise from treating them as cases of decisionmaking under risk, while adopting certain global empirical conditional probabilities as the relevant subjective probabihties. The most natural correct solutions employ the methodology of decisionmaking under uncertainty with lottery acts, with certain local empirical conditional (...) probabilities adopted as the relevant subjective probabilities. (shrink)

It is plausible that Newcomb problems in which causal maximizers and evidential maximizers would do different things would not be possible for ideal maximizers who are attentive to metatickles. An objection to Eells's first argument for this makes welcome a second. Against it I argue that even ideal evidential and causal maximizers would do different things in some non-dominance Newcomb problems; and that they would hope for different things in some third-person and non-action problems, which is relevant if (...) a good theory of rational choices of acts should fit smoothly into a good theory of rational desires for facts. (shrink)

Newcomb's Problem is a controversial paradox of decision theory. It is easily explained and easily understood, and there is a strong chance that most of us have actually faced it in some form or other. And yet it has proven as thorny and intractable a puzzle as much older and better-known philosophical problems of consciousness, scepticism and fatalism. It brings into very sharp and focused disagreement several long-standing philosophical theories on practical rationality, on the nature of free will, (...) and on the direction and analysis of causation. This volume introduces readers to the nature of Newcomb's Problem, and ten chapters by leading scholars present the most recent debates around the Problem and analyse its ramifications for decision theory, metaphysics, philosophical psychology and political science. Their chapters highlight the status of Newcomb's Problem as a live and continuing issue in modern philosophy. (shrink)

Newcomb’s problem is a decision puzzle whose difficulty and interest stem from the fact that the possible outcomes are probabilistically dependent on, yet causally independent of, the agent’s options. The problem is named for its inventor, the physicist William Newcomb, but first appeared in print in a 1969 paper by Robert Nozick [12]. Closely related to, though less well-known than, the Prisoners’ Dilemma, it has been the subject of intense debate in the philosophical literature. After three (...) decades, the issues remain unresolved. Newcomb’s problem is of genuine importance because it poses a challenge to the theoretical adequacy of orthodox Bayesian decision theory. It has led both to the development of causal decision theory and to efforts aimed at defending the adequacy of the orthodox theory. (shrink)

Richard Jeffrey said that Newcomb’s Problem may be seen “as a rock on which... Bayesianism... must founder” and the problem has been almost universally conceived as reconciling the science-fictional features of the decision problem with a plausible causal analysis. Later, Jeffrey renounced his earlier position that accepted Newcomb problems as genuine decision problems, suggesting “Newcomb problems are like Escher’s famous staircase”. We may interpret this to mean that we know there can be no such (...) thing, though we see no local flaw in the puzzle. In this paper, I develop the critique of Slezak to show that Jeffrey’s analogy is apt for a puzzle whose logical features can be precisely articulated and I propose an easily realizable experiment that convincingly supports this analysis. I suggest that these real-life analogs of Newcomb’s Problem have diverted attention from the essential function of the science-fiction of a predicting demon. Following Eells, similarities with realistic problems such as Prisoner’s Dilemma and common cause cases have suggested that Newcomb’s Problem may be given a coherent description and realized in some way consistent with classical causation. However, the peculiarity of the apparent link between one’s choice and the previously determined contents of the second box is the central, defining feature of Newcomb’s Problem. I argue that the predictor may not be merely a fiction providing insufficient “extra information” as both McKay and Levi suggest. Rather, I suggest that the decision problem permits a precise specification revealing the source of the notorious perplexity. Notwithstanding efforts to rescue the coherence of Newcomb’s Problem and a classical causal account, a simulation of the decision problem establishes the correctness of my analysis and, thereby, hopefully ending the debate. (shrink)

The 'Why ain'cha rich?' argument for one-boxing in Newcomb's problem allegedly vindicates evidential decision theory and undermines causal decision theory. But there is a good response to the argument on behalf of causal decision theory. I develop this response. Then I pose a new problem and use it to give a new 'Why ain'cha rich?' argument. Unlike the old argument, the new argument targets evidential decision theory. And unlike the old argument, the new argument is sound.

This paper aims to make three contributions to decision theory. First there is the hope that it will help to re-establish the legitimacy of the problem, pace various recent analyses provided by Maitzen and Wilson, Slezak and Priest. Second, after pointing out that analyses of the problem have generally relied upon evidence that is conditional on the taking of one particular option, this paper argues that certain assumptions implicit in those analyses are subtly flawed. As a third contribution, (...) the piece aims to draw attention to an important similarity between Newcomb’s problem and the toxin puzzle. In short, both problems illustrate the fact that you can have a reason to intend to φ without having a reason to actually φ. (shrink)

The more you think about it, the more baffling Newcomb's Problem becomes. To most people, at first it is obvious which solution is correct, but their confidence can be eroded easily. Only a puzzled few are torn between the two right from the start, and for years so was I. But at last, thanks to a certain metaargument, one solution came to seem obvious to me. And yet, imagining myself actually faced with Newcomb's choice, I started to (...) worry that I might experience just enough last-minute ambivalence to unsettle my confidence in that argument. Fortunately, I have found a strategy to ensure making the right choice when the chips are down.Not only is Newcomb's Problem puzzling in its own right, it is philosophically significant. The appeal of both solutions reflects a conflict between two plausible conceptions of rational choice. In making a decision, should one consider all of its probabilistic consequences or only its causal consequences? Each conception has its supporters, but some philosophers find them both defensible and see no hope of resolving the conflict. I think the conflict can be resolved, at least in the context of Newcomb's Problem, by properly assessing the relevant counterfactual conditionals. (shrink)

I present a game-theoretic way to understand the situation describing Newcomb’s Problem (NP) which helps to explain the intuition of both one-boxers and two-boxers. David Lewis has shown that the NP may be modelled as a Prisoners Dilemma game (PD) in which ‘cooperating’ corresponds to ‘taking one box’. Adopting relevant results from game theory, this means that one should take just one box if the NP is repeated an indefinite number of times, but both boxes if it is (...) a one-shot game. Causal decision theorists thus give the right answer for the one-shot situation, whereas the one-boxers’ solution applies to the indefinitely iterated case. Because Nozick’s set-up of the NP is ambiguous between a one-shot and a repeated game, both of these solutions may appear plausible – depending on whether one conceives of the situation as one-off or repeated. If the players’ aim is to maximize their payoffs, the symmetric structure of the PD implies that the two players will behave alike both when the game is one-shot and when it is played repeatedly. Therefore neither the observed outcome of both players selecting the same strategy (in the PD) nor, correspondingly, the predictor’s accurate prediction of this outcome (in the NP) is at all surprising. There is no need for a supernatural predictor to explain the NP phenomena. (shrink)

David Lewis argued that Newcomb’s Problem and the Prisoner’s Dilemma are “one and the same problem” or, to be more precise, that the Prisoner’s Dilemma is nothing else than “two Newcomb problems side by side” (Lewis Philosophy and Public Affairs 8:235–240, 1979 : 235). It has been objected that his argument fails to take into account certain epistemic asymmetries which undermine the one-problem thesis. Sobel ( 1985 ) acknowledges that many tokens satisfy the structural requirements (...) of both problems, while questioning the generality of the thesis. Bermúdez (Analysis 73:423–429, 2013 ), on the other hand, argues that there is a deeper structural conflict between the two problems in the sense that the epistemic requirements that give Newcomb’s Problem its force are precisely those that prevent it from being a Prisoner’s Dilemma. I argue that the epistemic asymmetry objections raised by Sobel and Bermúdez fail to undermine the one-problem thesis. A different type of objection raised by Bermúdez, one which relies on the contrast between parametric and strategic choices, fares no better. Although NP is a problem that has been primarily studied for its implications to decision theory, it contains enough game theoretic elements to justify the claim that a juxtaposition of two such problems can be thought of as a strategic game. (shrink)

Among various cases that equally admit of evidentialist reasoning, the supposedly evidentialist solution has varying degrees of intuitive attractiveness. I suggest that cooperative reasoning may account for the appeal of apparently evidentialist behavior in the cases in which it is intuitively attractive, while the inapplicability of cooperative reasoning may account for the unattractiveness of evidentialist behaviour in other cases. A collective causal power with respect to agreed outcomes, not evidentialist reasoning, makes cooperation attractive in the Prisoners' Dilemma. And a natural (...) though unwarranted assumption of such a power may account for the intuitive appeal of the one-box response in Newcomb's Problem. (shrink)

Newcomb’s problem involves a decision-maker faced with a choice and a predictor forecasting this choice. The agents’ interaction seems to generate a choice dilemma once the decision-maker seeks to apply two basic principles of rational choice theory : maximize expected utility ; adopt the dominant strategy. We review unsuccessful attempts at pacifying the dilemma by excluding Newcomb’s problem as an RCT-application, by restricting MEU and ADS, and by allowing for backward causation. A probability approach shows that (...) Newcomb’s original problem-formulation lacks causal information. This makes it impossible to specify the probability structure of Newcomb’s univocally. Once missing information is added, Newcomb’s problem and RCT re-align, thus explaining Newcomb’s problem as a seeming dilemma. Building on Wolpert and Benford :1637–1646, 2013), we supply additional details and offer a crucial correction to their formal proof. (shrink)

Newcomb’s Problem, Arif Ahmed (editor). Cambridge University Press, 2018, 233 pages.

According to David Lewis, the prisoner's dilemma (PD) and Newcomb's problem (NP) are really just one dilemma in two different forms (Lewis 1979). Lewis's argument for this conclusion is ingenious and has been widely accepted. However, it is flawed. As this paper shows, the considerations that Lewis brings to bear to show that the game he starts with is an NP equally show that the game is not a PD.